Alexander Dennis, a UK-based bus manufacturer, has achieved a significant milestone in electric bus technology.

Recent testing by Zemo Partnership has confirmed a 97% grid-to-wheel charging efficiency for the company's next-generation electric buses, marking the highest recorded efficiency in UK zero-emission bus certification to date.

This breakthrough is the result of a collaborative effort between Alexander Dennis and several key technology partners, including driveline supplier Voith Turbo, battery system provider Impact Clean Power Technology, and HVAC specialists Grayson Thermal Systems.

According to Alexander Dennis, the team focused on careful system integration and optimisation to achieve this exceptional level of efficiency.

The high charging efficiency complements the already impressive driveline energy consumption of Alexander Dennis's electric buses.

The Enviro400EV model was certified with a consumption of 0.67kWh/km over the UK Bus Cycle, while the Enviro100EV achieved 0.54kWh/km.

These advancements in both charging and driveline efficiencies are expected to significantly reduce the energy requirements for charging, potentially leading to lower operating costs for bus operators.

According to the independent data from Zemo Partnership testing, the Enviro400EV model could reduce energy costs by at least 14% compared to other certified electric double-decker buses of similar battery size under UK Bus Cycle testing conditions.

The new electric buses also boast a longer battery life, with a warrantable energy throughput of up to 1.6GWh, further contributing to a reduced total cost of ownership.

Alexander Dennis Group Engineering Director, Chris Gall, said: “We have focused on delivering benefits for our customers throughout the development of our next-generation electric buses.

“We’re delighted to announce a stunning 97% grid-to-wheel efficiency, certified by the Zemo Partnership’s zero-emission bus testing.

“This will minimise energy requirements and slash costs for customers by delivering sustained savings throughout their buses’ long operational lives.

“This is once again testament to the fantastic expertise of our engineering team and the collaborative working culture we have fostered with our key partners Voith Turbo, Impact Clean Power Technology and Grayson Thermal Systems.”